Weathertight ballast



Jan. 29, 1957 Filed March '7, 1956 W. L. R. HENDERSON WEATHERTIGHT BALLAST 2 Sheets-Sheet 1 IN VEN TOR.

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HIS ATTORNEY Jan. 29, 1957 w. R. HENDERSON WEATHERTIGHT BALLAST 2 Sheets-Sheet 2 Filed March 7, 1956 INVENTOR. My: [avg 10501: BY a HIS ATTORNEY United Patent G 2,779,496 WEATHERTIGHT BALLAST WayneLee Roy Henderson, Danville, 11]., assignor to General ElectricCompany, a corporation of New York Application March 7, 1955, fierial No. 570,174

6 Claims. (Cl. 220-332) My inventionrelates to casings or containers for in-. ductive devices and, more particularly, to casings for ballasts intended for outdoor application.

An object of the invention is to provide a metal casing for a ballast unit having no seams along the top and side edges exposed to admit seepage of water therethrough.

Another object is to provide a weathertight casing for a ballast unit which alsoserves as a sealed container for a hardening liquid-insulatingcompound, generally known as a potting? compound, used to embed the inductive device within the casing.

A further object is to provide a weathertight ballast unit in which a portion of the casing is utilized to house conveniently accessible connections to the ballast transformer therein while yet shielding these connections from rain and other weather conditions.

A still further object of the invention is to provide a weathertight ballast casing in which the parts of the easing are inexpensive sheet-metal drawings or stampings which may be easily'assembled to form the completed ballast.

In general, in accord with the invention, a weathertight ballast casing is provided in which a channel-shapedbody memberhas outwardly flared side flanges and a flat base member encloses the channel with its side edges continuously overlapping the flanges of the body member thereby to cover and seal the side seams between the two members. A cover member encloses the end of the channel with three side portions overlapping the corresponding sides of the body member and a fourth side portion extending laterally beyond and folded over the base member and the overlapped flanges of thebody member to cover and seal the end seams of these overlapped members. In this Way all of the top and side seams of the assembled casing are fully protected against the weather.

In accord with another feature of the invention, the folded-over side portion extension of the cover member is provided with mounting means formed therein.

In accord with a further feature of the invention, a plate-type baflle member or septum is located within the channel of the body member to divide the easing into two compartments, one of which houses the ballast components, such as the high-reactance transformer and any capacitors or resistors associated therewith, and the other serving as a junction box wherein connections to the ballast unit may be conveniently made and protected from the Weather. Suitable apertures in this baffle member and knock-outs in the portion of the casing defining the junction box are provided in order to accommodate the leads to and from the ballast unit. Another plate member, preferably similar to the internal bafile member but without lead accommodating apertures therein is employed to close the bottom end of the junction box portion of the casing.

The novel features believed characteristic of the intion are set forth in the appended claims. The invention itself, however, together with further objects and advantages thereof may be easily understood by referring 2V to the following descriptiontaken in connection with the accompanying drawings in which- Figure 1 is aperspective exploded view of the parts of a ballast casing embodying the invention,

Figure 2 is a plan view of an assembledballast unit employing the casing of Figure 1 showing the internal location and connections of the ballasting components, and

Figure 3 is a side view of the ballast casing of Figure 2.

Referring to Figure 1, a Weathertight casing 1G embodying the invention is shown as comprising a longitudinally extending channel-shaped body member 11, a base member 12 and endcovermember 13. Channel-shaped body member 11 has its opposite sides 14 outwardly flared along its longitudinally extending edge portions to form longitudinally extending continuous flanges, 15. Base member 12 comprises a flat plate 16 having opposite sides 17 folded inwardly on the same side of plate 16 to overlap flanges 15 continuously and preferably coextensively; Althoughshown in an exploded view in Figure 1 it will be appreciatedthat flanges 15 fit within grooves 18 formed by folded-over sides 17 of base member 12 when in assembled relation as illustrated, for example, in Figures 2 and 3. The overlapping of flanges 15 by inturned sides 17 serves not only to fasten the body and base members together, but also covers the side edges 19 ofv these flanges 15 and provides a tortuous path for any seepage of water into the interior of the casing 19 through these overlapped flanges. One end 12 of base member 12 extends beyond the inturned sides 17 and contains suitable mounting means such as upwardly indented groove 16'.

Cover member 13 has three outer or side portions 26?, 21 and 22 drawn or folded down to form an integral three-sided flange adapted to overlap and snugly em-. brace the three corresponding end portions 20', 21' and 22' of the channel-shaped body member 11. These three side portions 20, 21 and 22. of cover member 13 thus serve to enclose and seal the .three edges 23, 24 and 25 at one end of this body member 11.

Cover member 13 also has a fourth outer or side portion 26 havingend sections 27 extending laterally beyond the overlapped flanges 15 of body member 11. The outer or side-edge-adjacent region 28 of this fourth side portion 26 of cover member 13 is folded to overlie the adjacent end of base member 12 leaving portions 29 of the end sections 27 extending in the same plane as central plate 13' to cover and overlie the ends of the overlapping flanges 15 and base member side portions 17 so as to seal the end seams therebetween. The opposite side portions 20 and 22 terminate short of the foldedover region 28 of the fourth side portion 26 to permit laterally extending portions 29 of end section 7 to remain integral with central plate 13'. The folded-over regions 28 may have mounting means 30 formed in the end sections 27 thereof, which preferably take the form of grooves upwardly indented toward the central plate 13' of the cover member 13 in order that the casing 19 may be easily hung and secured with its major dimension in a vertical plane so that cover member 13 is at the top, as illustrated in Figure 1.

Within casing 10, a plate member 32 is provided as a septum dividing the easing into two compartments 33 and 34. As illustrated in Figures 2 and 3, compartment 33 is used to house the inductive device 35 and other ballasting components of the unit such as capacitor 35' while compartment 34 is used as a junction box for the connections between wires running to and from the ballasting components. Plate member 32 also functions as a battle for containing a conventional hardening insulating liquid 36, such as hot asphalt, poured into compartment 33 to embed the ballast components 35, 35 and to improve heat dissipation therefrom.

The four sides 37 of plate member 32 are bent or drawn substantially perpendicular to the central portion 32 to form a shallow-box-type configuration of considerable strength and rigidity. Three of these sides 37 are fastened, such as by spot welding to the corresponding sides of channel member 11. Apertures 38 for accommodating leads from the ballast components may be punched or extruded in the central portion of plate 32.

Another plate member 40 is preferably inserted as a snug fit within the bottom end 41 of casing to enclose the junction box compartment 34. Plate member 40 is similar to plate member 32 with the exception that the lead-accommodating apertures 38 are replaced by a small square hole 39 provided to accommodate the tip of a screwdriver or other tool to be used in removing this end plate member 40. Perforatedly outlined sections 42 are preferably also formed in one or more sides of channelshaped body member 11 as knock-outs leaving apertures 42 for accommodating leads running to or from compartment 34, as shown in Figure 2.

In assemblying a ballast unit with casing 10, the dividing plate member 32 is first located within body member 11 at a proper distance from the upper end of casing 10 to accommodate all of the ballasting components and is then fastened therein such as by spot Welding. Cover member 13 is pressed over the upper end of body member 11 and the three side portions 20, 21 and 22 fastened thereto such as by spot welding. The ballasting components including inductive device 35 and capacitor 35' are placed within compartment 33 with the leads thereof threaded through apertures 38 in the dividing plate member 32. The hardening insulating liquid 36 or potting compound is poured over the ballasting components to fill all voids within compartment 33. Base member 12 is then slid onto the body member 11 by engaging the bottom end of flanges within the top end of grooves 18 and moving the two members longitudinally relative to one another until the top of base member 12 moves beneath folded-over portion 28 and hits the central plate 13 of cover member 13. Alternatively, these body and base members may be clamped together before cover member 13 is assembled and the ballasting components and potting compound inserted from the open top. As is well known in the art, the viscosity and hardening charac- ,teristics of the hot potting compound 36 is such that it seeps partially through apertures 38 to surround the leads 43 and quickly hardens to seal these apertures 33. The folded-over portion 28 of cover member 13 is then secuerd to base member 12, such as by spot welding, and

the bottom end plate member 40 is pressed within the bottom end of casing 10 to enclose compartment 34.

When it is desired to use compartment 34 as a junction box, bottom end plate member 40 is removed by a screwdriver or other tool and incoming leads 45 threaded through punched-out apertures 42 in a side of body member 11. Connections 44 are then made between the outgoing and incoming leads 43 and 45 and the bottom plate member 40 replaced.

While I have described above a particular preferred embodiment of my invention, many modifications may be made. It is to be understood, therefore, that I intend by the appended claims to cover all such modifications as fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A weathertight casing for a ballast unit comprising a channel-shaped body member having outwardly flared flanges along opposite longitudinal edges, a base member covering the channel of said body member with its side edges overlapping said flanges, and a cover member having three side portions overlapping the three sides of one end of said body member and a fourth side portion overlying the base member and the flanges of said body member overlapped by said base member to cover one end of said casing and seal the end seams of said overlapped flanges.

2. The weather tight casing of claim 1 including a plate member fastened to said body member across the channel thereof to divide said casing into a compartment for housing ballasting components and a compartment for housing connections thereto.

3. A casing for a ballast unit comprising a channelshaped body member having outwardly flared flanges along opposite longitudinal edges, a base member cover ing the channel of said body member with its side edges coextensively overlapping said flanges of said body member, and a cover member [or one end of said casing having three side portions overlapping said body member and a fourth side portion folded over said base member, said fourth folded-over side portion extending laterally beyond the flanges of said channel member with mounting means formed in said lateral extensions thereof.

4. A weathertight casing for a ballast unit comprising a channel-shaped body member having outwardly flared flanges along opposite longitudinal edges, a base member covering the channel of said body member with its side edges overlapping said flanges coextensive with one end thereof, and a cover member for said one end of said casing having three side portions overlapping the end portions of said body member, and a fourth side portion overlying said base member, said fourth side portion having end sections extending laterally beyond the overlapped flanges of body member with portions thereof covering the end seams of said overlapped flanges.

5. The weatherproof casing of claim 4 including a plate member fastened to said body member across the channel thereof to divide said casing into a compartment for housing ballasting components and a compartment for housing connections thereto.

6. A weatherproof casing for a ballast unit comprising a longitudinally extending channel-shaped body member, a base member covering the channel of said channel member with its sides continuously overlapping the side edge portions of said body member, a plate member within said channel fastened to said body member and dividing said casing into two compartments, and a cover member for one end of said casing having three side portions overlapping the three sides of said body member and a fourth side portion overlying the base member and the ends of the overlapped side edge portions of the body member to seal the end seams of said overlapped side edge portions.

References Cited in the file of this patent UNITED STATES PATENTS 1,235,069 Skinner July 31, 1917 1,296,653 Griswold Mar. 11, 1919 1,352,002 Jones Sept. 7, 1920 2,489,245 Sola Nov. 22, 1949 2,550,362 Logie Apr. 24, 1951 2,701,174 Franks Feb. 1, 1955 

